On the paper
Read which tax year the notice names and confirm what your records show you filed for that year.
Check the year against your own filing record before anything else. A CP59 for a year you filed on paper, filed late, or filed from an address the IRS did not have is a records problem, and the proof of filing closes it. A CP59 for a year you genuinely skipped is a filing problem, and the answer is the return.
Find the date printed on your notice or letter. The paper notice and the current official IRS instructions control, even where this page differs.
Where this notice comes from
The IRS builds these notices from the information returns filed under your identification number. A year with wage or payment records and no return generates the inquiry.
The refund side of an unfiled year is time-limited. A refund not claimed within the statutory period is not recoverable, so an old unfiled year that would have produced a refund can quietly become worth nothing.
If no return arrives, the IRS may prepare a substitute return from the information it has. A substitute return uses no deductions or credits the taxpayer would have claimed, so the figure it produces is generally higher than a filed return would show.
General next steps
- Confirm whether a return was required for that year under the filing thresholds for your status.
- If it was, prepare and file it, and expect the balance or refund to follow separately.
- If it was not, use the response route the notice gives to say so and keep a copy.
Timing
The IRS page for CP59, checked September 10, 2026, gives no general period. It states that you do not have to do anything if you filed the return within the last eight weeks, and it notes that the Internal Revenue Code sets strict time limits for claiming a refund or credit. The date printed on the notice controls; do not calculate a deadline from this page.
What CP59 does not mean
CP59 is not an assessment. It does not say you owe anything, because without a return the IRS has not computed anything. It also does not mean the IRS has prepared a return for you; that step, when it happens, arrives as its own notice with proposed figures.
What this page cannot tell you
This page cannot tell you whether you were required to file for a given year or what the IRS will accept as an explanation.
Matters involving unfiled returns
This letter concerns a missing return. Read Matters involving unfiled returns.
Official sources
If anything on this page differs from your notice or from current IRS instructions, follow the notice and the IRS.
Common questions
I filed that year. What proof does the IRS want?
The acceptance record from electronic filing or the certified mail receipt for a paper return. The IRS also says you need do nothing if you filed within the last eight weeks, because processing may not have caught up.
What is a substitute return?
It is a return the IRS prepares from the information returns it holds when none is filed. It generally allows no deductions or credits beyond the minimum, so it usually produces a larger balance than a filed return would.
The year would have produced a refund. Is it still worth filing?
The Internal Revenue Code sets time limits for claiming a refund or credit. Whether a particular year is still within that period depends on the dates, and filing is the only way to claim it at all.